Seamus Young scored two minutes into the match for Victoria (19-28-0-1), which fell into the bottom of the West Division following Utah's 4-2 win over Long Beach. Tuomas Mikkonen replied before the period was through for Idaho (24-17-2-1).
Steelheads goalie Steve Silverthorn blocked 30 shots, while Bryan Bridges made 19 saves for Victoria.
Neither team was able to capitalize on the power play, with Idaho missing on two chances and the Salmon Kings failing to convert on any of their four opportunities.
The teams resume their series on Friday and Saturday nights in Boise.